/****************************************************************************************
| Description: demo program bootloader interface source file
| File Name: boot.c
|
|----------------------------------------------------------------------------------------
| C O P Y R I G H T
|----------------------------------------------------------------------------------------
| Copyright (c) 2011 by Feaser http://www.feaser.com All rights reserved
|
|----------------------------------------------------------------------------------------
| L I C E N S E
|----------------------------------------------------------------------------------------
| This file is part of OpenBLT. OpenBLT is free software: you can redistribute it and/or
| modify it under the terms of the GNU General Public License as published by the Free
| Software Foundation, either version 3 of the License, or (at your option) any later
| version.
|
| OpenBLT is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
| without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
| PURPOSE. See the GNU General Public License for more details.
|
| You should have received a copy of the GNU General Public License along with OpenBLT.
| If not, see .
|
| A special exception to the GPL is included to allow you to distribute a combined work
| that includes OpenBLT without being obliged to provide the source code for any
| proprietary components. The exception text is included at the bottom of the license
| file .
|
****************************************************************************************/
/****************************************************************************************
* Include files
****************************************************************************************/
#include "header.h" /* generic header */
/****************************************************************************************
** NAME: BootActivate
** PARAMETER: none
** RETURN VALUE: none
** DESCRIPTION: Bootloader activation function.
**
****************************************************************************************/
static void BootActivate(void)
{
void (*pEntryFromProgFnc)(void);
/* set pointer to the address of function EntryFromProg in the bootloader */
pEntryFromProgFnc = (void*)0x00000040;
/* call EntryFromProg to activate the bootloader. */
pEntryFromProgFnc();
} /*** end of BootActivate ***/
#if (BOOT_COM_UART_ENABLE > 0)
/****************************************************************************************
* U N I V E R S A L A S Y N C H R O N O U S R X T X I N T E R F A C E
****************************************************************************************/
/****************************************************************************************
* Macro definitions
****************************************************************************************/
#define UART_DLAB (0x80) /* divisor latch access bit */
#define UART_MODE_8N1 (0x03) /* 8 data and 1 stop bit, no parity */
#define UART_FIFO_RX1 (0x07) /* FIFO reset and RX FIFO 1 deep */
#define UART_RDR (0x01) /* receiver data ready */
/****************************************************************************************
* Function prototypes
****************************************************************************************/
static unsigned char UartReceiveByte(unsigned char *data);
/****************************************************************************************
** NAME: BootComInit
** PARAMETER: none
** RETURN VALUE: none
** DESCRIPTION: Initializes the UART communication interface
**
****************************************************************************************/
void BootComInit(void)
{
unsigned long baud_reg_value; /* baudrate register value */
/* configure P0.0 for UART0 Tx and P0.1 for UART0 Rx functionality */
PINSEL0 |= 0x05;
/* disable UART related interrupt generation. this driver works in polling mode */
U0IER = 0;
/* clear interrupt id register */
U0IIR = 0;
/* clear line status register */
U0LSR = 0;
/* set divisor latch DLAB = 1 so buadrate can be configured */
U0LCR = UART_DLAB;
/* Baudrate calculation:
* y = BOOT_CPU_SYSTEM_SPEED_KHZ * 1000 / 16 / BOOT_COM_UART_BAUDRATE and add
* smartness to automatically round the value up/down using the following trick:
* y = x/n can round with y = (x + (n + 1)/2 ) / n
*/
baud_reg_value = (((BOOT_CPU_SYSTEM_SPEED_KHZ*1000/16)+ \
((BOOT_COM_UART_BAUDRATE+1)/2))/BOOT_COM_UART_BAUDRATE);
/* write the calculated baudrate selector value to the registers */
U0DLL = (unsigned char)baud_reg_value;
U0DLM = (unsigned char)(baud_reg_value >> 8);
/* configure 8 data bits, no parity and 1 stop bit and set DLAB = 0 */
U0LCR = UART_MODE_8N1;
/* enable and reset transmit and receive FIFO. necessary for UART operation */
U0FCR = UART_FIFO_RX1;
} /*** end of BootComInit ***/
/****************************************************************************************
** NAME: BootComCheckActivationRequest
** PARAMETER: none
** RETURN VALUE: none
** DESCRIPTION: Receives the CONNECT request from the host, which indicates that the
** bootloader should be activated and, if so, activates it.
**
****************************************************************************************/
void BootComCheckActivationRequest(void)
{
static unsigned char xcpCtoReqPacket[BOOT_COM_UART_RX_MAX_DATA+1];
static unsigned char xcpCtoRxLength;
static unsigned char xcpCtoRxInProgress = 0;
/* start of cto packet received? */
if (xcpCtoRxInProgress == 0)
{
/* store the message length when received */
if (UartReceiveByte(&xcpCtoReqPacket[0]) == 1)
{
/* indicate that a cto packet is being received */
xcpCtoRxInProgress = 1;
/* reset packet data count */
xcpCtoRxLength = 0;
}
}
else
{
/* store the next packet byte */
if (UartReceiveByte(&xcpCtoReqPacket[xcpCtoRxLength+1]) == 1)
{
/* increment the packet data count */
xcpCtoRxLength++;
/* check to see if the entire packet was received */
if (xcpCtoRxLength == xcpCtoReqPacket[0])
{
/* done with cto packet reception */
xcpCtoRxInProgress = 0;
/* check if this was an XCP CONNECT command */
if ((xcpCtoReqPacket[1] == 0xff) && (xcpCtoReqPacket[2] == 0x00))
{
/* connection request received so start the bootloader */
BootActivate();
}
}
}
}
} /*** end of BootComCheckActivationRequest ***/
/****************************************************************************************
** NAME: UartReceiveByte
** PARAMETER: data pointer to byte where the data is to be stored.
** RETURN VALUE: 1 if a byte was received, 0 otherwise.
** DESCRIPTION: Receives a communication interface byte if one is present.
**
****************************************************************************************/
static unsigned char UartReceiveByte(unsigned char *data)
{
/* check if a new byte was received by means of the RDR-bit */
if((U0LSR & UART_RDR) != 0)
{
/* store the received byte */
data[0] = U0RBR;
/* inform caller of the newly received byte */
return 1;
}
/* inform caller that no new data was received */
return 0;
} /*** end of UartReceiveByte ***/
#endif /* BOOT_COM_UART_ENABLE > 0 */
#if (BOOT_COM_CAN_ENABLE > 0)
/****************************************************************************************
* C O N T R O L L E R A R E A N E T W O R K I N T E R F A C E
****************************************************************************************/
/****************************************************************************************
* Macro definitions
****************************************************************************************/
#define CAN_TBS1 (0x00000004) /* transmit buffer 1 idle */
#define CAN_TCS1 (0x00000008) /* transmit buffer 1 complete */
#define CAN_RRB (0x04) /* receive buffer release */
#define CAN_RBS (0x01) /* receive buffer status */
#define CAN_TR (0x01) /* transmission request */
#define CAN_STB1 (0x20) /* select tx buffer 1 for transmit */
/****************************************************************************************
* Type definitions
****************************************************************************************/
typedef struct t_can_bus_timing
{
unsigned char tseg1; /* CAN time segment 1 */
unsigned char tseg2; /* CAN time segment 2 */
} tCanBusTiming; /* bus timing structure type */
/****************************************************************************************
* Local constant declarations
****************************************************************************************/
/* According to the CAN protocol 1 bit-time can be made up of between 8..25 time quanta
* (TQ). The total TQ in a bit is SYNC + TSEG1 + TSEG2 with SYNC always being 1.
* The sample point is (SYNC + TSEG1) / (SYNC + TSEG1 + SEG2) * 100%. This array contains
* possible and valid time quanta configurations with a sample point between 68..78%.
*/
static const tCanBusTiming canTiming[] =
{ /* TQ | TSEG1 | TSEG2 | SP */
/* ------------------------- */
{ 5, 2 }, /* 8 | 5 | 2 | 75% */
{ 6, 2 }, /* 9 | 6 | 2 | 78% */
{ 6, 3 }, /* 10 | 6 | 3 | 70% */
{ 7, 3 }, /* 11 | 7 | 3 | 73% */
{ 8, 3 }, /* 12 | 8 | 3 | 75% */
{ 9, 3 }, /* 13 | 9 | 3 | 77% */
{ 9, 4 }, /* 14 | 9 | 4 | 71% */
{ 10, 4 }, /* 15 | 10 | 4 | 73% */
{ 11, 4 }, /* 16 | 11 | 4 | 75% */
{ 12, 4 }, /* 17 | 12 | 4 | 76% */
{ 12, 5 }, /* 18 | 12 | 5 | 72% */
{ 13, 5 }, /* 19 | 13 | 5 | 74% */
{ 14, 5 }, /* 20 | 14 | 5 | 75% */
{ 15, 5 }, /* 21 | 15 | 5 | 76% */
{ 15, 6 }, /* 22 | 15 | 6 | 73% */
{ 16, 6 }, /* 23 | 16 | 6 | 74% */
{ 16, 7 }, /* 24 | 16 | 7 | 71% */
{ 16, 8 } /* 25 | 16 | 8 | 68% */
};
/****************************************************************************************
** NAME: CanGetSpeedConfig
** PARAMETER: baud The desired baudrate in kbps. Valid values are 10..1000.
** btr Pointer to where the value for register CANxBTR will be stored.
** RETURN VALUE: 1 if the CAN bustiming register values were found, 0 otherwise.
** DESCRIPTION: Search algorithm to match the desired baudrate to a possible bus
** timing configuration.
**
****************************************************************************************/
static unsigned char CanGetSpeedConfig(unsigned short baud, unsigned long *btr)
{
unsigned short prescaler;
unsigned char cnt;
/* loop through all possible time quanta configurations to find a match */
for (cnt=0; cnt < sizeof(canTiming)/sizeof(canTiming[0]); cnt++)
{
if ((BOOT_CPU_SYSTEM_SPEED_KHZ % (baud*(canTiming[cnt].tseg1+canTiming[cnt].tseg2+1))) == 0)
{
/* compute the prescaler that goes with this TQ configuration */
prescaler = BOOT_CPU_SYSTEM_SPEED_KHZ/(baud*(canTiming[cnt].tseg1+canTiming[cnt].tseg2+1));
/* make sure the prescaler is valid */
if ( (prescaler > 0) && (prescaler <= 1024) )
{
/* store the prescaler and bustiming register value */
*btr = prescaler - 1;
*btr |= ((canTiming[cnt].tseg2 - 1) << 20) | ((canTiming[cnt].tseg1 - 1) << 16);
/* found a good bus timing configuration */
return 1;
}
}
}
/* could not find a good bus timing configuration */
return 0;
} /*** end of CanGetSpeedConfig ***/
/****************************************************************************************
** NAME: BootComInit
** PARAMETER: none
** RETURN VALUE: none
** DESCRIPTION: Initializes the CAN communication interface
**
****************************************************************************************/
void BootComInit(void)
{
unsigned long btr_reg_value;
/* configure acceptance filter for bypass mode so it receives all messages */
CANAFMR = 0x00000002L;
/* take CAN controller offline and go into reset mode */
CAN1MOD = 1;
/* disable all interrupts. driver only needs to work in polling mode */
CAN1IER = 0;
/* reset CAN controller status */
CAN1GSR = 0;
/* configure the bittiming */
if (CanGetSpeedConfig(BOOT_COM_CAN_BAUDRATE/1000, &btr_reg_value) == 1)
{
/* write the bittiming configuration to the register */
CAN1BTR = btr_reg_value;
}
/* enter normal operating mode and synchronize to the CAN bus */
CAN1MOD = 0;
} /*** end of BootComInit ***/
/****************************************************************************************
** NAME: BootComCheckActivationRequest
** PARAMETER: none
** RETURN VALUE: none
** DESCRIPTION: Receives the CONNECT request from the host, which indicates that the
** bootloader should be activated and, if so, activates it.
**
****************************************************************************************/
void BootComCheckActivationRequest(void)
{
unsigned char data[2];
/* check if a new message was received */
if ((CAN1SR & CAN_RBS) == 0)
{
return;
}
/* see if this is the message identifier that we are interested in */
if (CAN1RID != BOOT_COM_CAN_RX_MSG_ID)
{
return;
}
/* store the message data */
data[0] = (unsigned char)CAN1RDA;
data[1] = (unsigned char)(CAN1RDA >> 8);
/* release the receive buffer */
CAN1CMR = CAN_RRB;
/* check if this was an XCP CONNECT command */
if ((data[0] == 0xff) && (data[1] == 0x00))
{
/* connection request received so start the bootloader */
BootActivate();
}
} /*** end of BootComCheckActivationRequest ***/
#endif /* BOOT_COM_CAN_ENABLE > 0 */
/*********************************** end of boot.c *************************************/